Systemic chemotherapy remains the mainstay of treatment for patient with metastatic anal cancer. The National Comprehensive Cancer Network (NCCN) Guidelines currently recommend cisplatin and 5FU chemotherapy as first-line treatment of metastatic squamous cell carcinoma (SCC). This is largely based on a study of 19 patients treated with cisplatin 100 mg/m2 and infusional 5FU 1 gm/m2/day over 5 days with a 66% response rate; there was 1 complete response and 11 partial responses in addition to 4 patients with stable disease. There have also been a number of case reports demonstrating a benefit with the cisplatin/5FU combination. This is the best researched, although not extensively supported, regimen for anal cancer.
Recently the oral fluoropyrimidine capecitabine(Xeloda) has been substituted for 5FU in a number of solid tumours, and, extrapolating from this data, many oncologists use capecitabine with cisplatin rather than 5FU. This has a number of advantages for patients, including ease of administration and possibly greater efficacy. Unfortunately, however, there is no literature support for this substitution.
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